大気大循環における気候ジャンプ

Abstract

Climatic jump implies an abrupt change of multiyear averages. This is a new conceptin the climat diagnosis, introduced recently by the present authors, in contrast to widelyaccepted premise of continuous changes of climate. The previously proposed method ofdetecting the climate jumps of statistical significance is improved, so as to avoid a mistakingany oscillatory change or long-term trend. This method is applied to the EOF analysisresults of monthly mean data of sea-level pressure over the Northern Hemisphere, and statis-tically significant jumps are detected around 1920 and 1950. These climatic jumps are associatedwith abrupt changes of Icelandic and Aleutian Lows.